diff --git a/arangod/Aql/AstNode.cpp b/arangod/Aql/AstNode.cpp
index e38e6f6586..95106986f7 100644
--- a/arangod/Aql/AstNode.cpp
+++ b/arangod/Aql/AstNode.cpp
@@ -238,7 +238,8 @@ static TRI_json_type_e GetNodeCompareType (AstNode const* node) {
 ////////////////////////////////////////////////////////////////////////////////
 
 int triagens::aql::CompareAstNodes (AstNode const* lhs, 
-                                    AstNode const* rhs) {
+                                    AstNode const* rhs,
+                                    bool compareUtf8) {
   if (lhs->type == NODE_TYPE_ATTRIBUTE_ACCESS) {
     lhs = ResolveAttribute(lhs);
   }
@@ -251,6 +252,7 @@ int triagens::aql::CompareAstNodes (AstNode const* lhs,
 
   if (lType != rType) {
     int diff = static_cast<int>(lType) - static_cast<int>(rType);
+
     TRI_ASSERT_EXPENSIVE(diff != 0);
 
     if (diff < 0) {
@@ -268,6 +270,7 @@ int triagens::aql::CompareAstNodes (AstNode const* lhs,
   }
   else if (lType == TRI_JSON_BOOLEAN) {
     int diff = static_cast<int>(lhs->getIntValue() - rhs->getIntValue());
+
     if (diff != 0) {
       if (diff < 0) {
         return -1; 
@@ -286,7 +289,10 @@ int triagens::aql::CompareAstNodes (AstNode const* lhs,
     }
   }
   else if (lType == TRI_JSON_STRING) {
-    return TRI_compare_utf8(lhs->getStringValue(), rhs->getStringValue());
+    if (compareUtf8) {
+      return TRI_compare_utf8(lhs->getStringValue(), rhs->getStringValue());
+    }
+    return strcmp(lhs->getStringValue(), rhs->getStringValue());
   }
   else if (lType == TRI_JSON_ARRAY) {
     size_t const numLhs = lhs->numMembers();
@@ -294,7 +300,8 @@ int triagens::aql::CompareAstNodes (AstNode const* lhs,
     size_t const n = ((numLhs > numRhs) ? numRhs : numLhs);
  
     for (size_t i = 0; i < n; ++i) {
-      int res = triagens::aql::CompareAstNodes(lhs->getMember(i), rhs->getMember(i));
+      int res = triagens::aql::CompareAstNodes(lhs->getMember(i), rhs->getMember(i), compareUtf8);
+
       if (res != 0) {
         return res;
       }    
@@ -314,7 +321,9 @@ int triagens::aql::CompareAstNodes (AstNode const* lhs,
     // for array AstNodes)
     auto lJson = lhs->toJsonValue(TRI_UNKNOWN_MEM_ZONE);
     auto rJson = lhs->toJsonValue(TRI_UNKNOWN_MEM_ZONE);
-    int res = TRI_CompareValuesJson(lJson, rJson, true);
+
+    int res = TRI_CompareValuesJson(lJson, rJson, compareUtf8);
+
     if (lJson != nullptr) {
       TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, lJson);
     }
@@ -590,11 +599,12 @@ void AstNode::sort () {
 
   auto const ptr = members._buffer;
   auto const end = ptr + members._length;
+
   std::sort(ptr, end, [] (void const* lhs, void const* rhs) {
     auto const l = static_cast<AstNode const*>(lhs);
     auto const r = static_cast<AstNode const*>(rhs);
 
-    return (triagens::aql::CompareAstNodes(l, r) < 0);
+    return (triagens::aql::CompareAstNodes(l, r, false) < 0);
   });
 
   setFlag(DETERMINED_SORTED, VALUE_SORTED);
@@ -606,6 +616,7 @@ void AstNode::sort () {
 
 std::string const& AstNode::getTypeString () const {
   auto it = TypeNames.find(static_cast<int>(type));
+
   if (it != TypeNames.end()) {
     return (*it).second;
   }
diff --git a/arangod/Aql/AstNode.h b/arangod/Aql/AstNode.h
index 5f198ded6d..253fd4af2b 100644
--- a/arangod/Aql/AstNode.h
+++ b/arangod/Aql/AstNode.h
@@ -751,7 +751,7 @@ namespace triagens {
 
     };
 
-    int CompareAstNodes (AstNode const*, AstNode const*);
+    int CompareAstNodes (AstNode const*, AstNode const*, bool);
   }
 }
 
diff --git a/arangod/Aql/ExecutionBlock.cpp b/arangod/Aql/ExecutionBlock.cpp
index 9172aece6a..03892f9ca8 100644
--- a/arangod/Aql/ExecutionBlock.cpp
+++ b/arangod/Aql/ExecutionBlock.cpp
@@ -1059,13 +1059,18 @@ IndexRangeBlock::IndexRangeBlock (ExecutionEngine* engine,
     _hasV8Expression(false) {
 
   auto trxCollection = _trx->trxCollection(_collection->cid());
+
   if (trxCollection != nullptr) {
     _trx->orderBarrier(trxCollection);
   }
-     
-  for (size_t i = 0; i < en->_ranges.size(); i++) {
+    
+  std::vector<std::vector<RangeInfo>> const& orRanges = en->_ranges;
+  size_t const n = orRanges.size(); 
+
+  for (size_t i = 0; i < n; i++) {
     _condition->emplace_back(IndexAndCondition());
-    for (auto ri: en->_ranges[i]) {
+
+    for (auto const& ri: en->_ranges[i]) {
       _condition->at(i).emplace_back(ri.clone());
     }
   }
@@ -1074,7 +1079,6 @@ IndexRangeBlock::IndexRangeBlock (ExecutionEngine* engine,
     removeOverlapsIndexOr(*_condition);
   }
 
-  std::vector<std::vector<RangeInfo>> const& orRanges = en->_ranges;
   TRI_ASSERT(en->_index != nullptr);
 
   _allBoundsConstant.clear();
@@ -1083,8 +1087,9 @@ IndexRangeBlock::IndexRangeBlock (ExecutionEngine* engine,
   // Detect, whether all ranges are constant:
   for (size_t i = 0; i < orRanges.size(); i++) {
     bool isConstant = true;
+
     std::vector<RangeInfo> const& attrRanges = orRanges[i];
-    for (auto r : attrRanges) {
+    for (auto const& r : attrRanges) {
       isConstant &= r.isConstant();
     }
     _anyBoundVariable |= ! isConstant;
diff --git a/arangod/Aql/OptimizerRules.cpp b/arangod/Aql/OptimizerRules.cpp
index e96b64e5ef..039a1665af 100644
--- a/arangod/Aql/OptimizerRules.cpp
+++ b/arangod/Aql/OptimizerRules.cpp
@@ -1679,8 +1679,8 @@ static RangeInfoMapVec* BuildRangeInfo (ExecutionPlan* plan,
       if (enumCollVar != nullptr) {
         foundSomething = true;
 
-        std::unordered_set<Variable*> varsUsed 
-          = Ast::getReferencedVariables(lhs);
+        std::unordered_set<Variable*>&& varsUsed = Ast::getReferencedVariables(lhs);
+
         if (varsUsed.find(const_cast<Variable*>(enumCollVar)) 
             == varsUsed.end()) {
           // Found a multiple attribute access of a variable and an
@@ -1847,9 +1847,7 @@ static RangeInfoMapVec* BuildRangeInfo (ExecutionPlan* plan,
             for (size_t i = 0; i < n; i++) {
               RangeInfo ri(enumCollVar->name, 
                            attr.substr(0, attr.size() - 1), 
-                           RangeInfoBound(rhs->getMember(i), true),
-                           RangeInfoBound(rhs->getMember(i), true), 
-                           true);
+                           RangeInfoBound(rhs->getMember(i), true));
               // the following does not seem to be necessary here, but will slow things down
               // considerably if the array is very big
               // rimv->differenceRangeInfo(ri);
@@ -1863,9 +1861,7 @@ static RangeInfoMapVec* BuildRangeInfo (ExecutionPlan* plan,
           else { 
             RangeInfo ri(enumCollVar->name, 
                          attr.substr(0, attr.size() - 1), 
-                         RangeInfoBound(rhs, true),
-                         RangeInfoBound(rhs, true), 
-                         true);
+                         RangeInfoBound(rhs, true));
             rimv->differenceRangeInfo(ri);
             if (ri.isValid()) { 
               std::unique_ptr<RangeInfoMap> temp(new RangeInfoMap(ri));
@@ -2105,14 +2101,14 @@ class FilterToEnumCollFinder : public WalkerWorker<ExecutionNode> {
             // results), for example
             // x.a == 1 || y.c == 2 || x.a == 3
             if (_rangeInfoMapVec->isMapped(var->name)) {
-              std::vector<size_t> const validPos = _rangeInfoMapVec->validPositions(var->name);
+              std::vector<size_t>&& validPos = _rangeInfoMapVec->validPositions(var->name);
 
               // are any of the RangeInfoMaps in the vector valid? 
 
               if (! _canThrow) {
                 if (validPos.empty()) { // ranges are not valid . . . 
                   auto parents = node->getParents();
-                  for (auto x : parents) {
+                  for (auto const& x : parents) {
                     auto noRes = new NoResultsNode(_plan, _plan->nextId());
                     _plan->registerNode(noRes);
                     _plan->insertDependency(x, noRes);
@@ -2127,8 +2123,7 @@ class FilterToEnumCollFinder : public WalkerWorker<ExecutionNode> {
 
                   // note: prefixes are only used for skiplist indexes
                   // for all other index types, the prefix value will always be 0
-                  node->getIndexesForIndexRangeNode(
-                      _rangeInfoMapVec->attributes(var->name), idxs, prefixes);
+                  node->getIndexesForIndexRangeNode(_rangeInfoMapVec->attributes(var->name), idxs, prefixes);
                   // make one new plan for every index in <idxs> that replaces the
                   // enumerate collection node with a IndexRangeNode ... 
 
@@ -4347,7 +4342,7 @@ struct RemoveRedundantOr {
   // returns false if the existing value is better and true if the input value is
   // better
   bool compareBounds (AstNodeType type, AstNode const* value, int lowhigh) { 
-    int cmp = CompareAstNodes(bestValue, value);
+    int cmp = CompareAstNodes(bestValue, value, true);
 
     if (cmp == 0 && (isInclusiveBound(comparison) != isInclusiveBound(type))) {
       return (isInclusiveBound(type) ? true : false);
diff --git a/arangod/Aql/RangeInfo.cpp b/arangod/Aql/RangeInfo.cpp
index d2cbe6c6f7..3568c36499 100644
--- a/arangod/Aql/RangeInfo.cpp
+++ b/arangod/Aql/RangeInfo.cpp
@@ -427,7 +427,7 @@ void RangeInfoMap::attributes (std::unordered_set<std::string>& set,
   std::unordered_map<std::string, RangeInfo> const* map = find(var);
 
   if (map != nullptr) {
-    for (auto x: *map) {
+    for (auto const& x: *map) {
       set.emplace(x.first);
     }
   }
@@ -527,7 +527,9 @@ bool RangeInfoMapVec::isMapped (std::string const& var) const {
 std::vector<size_t> RangeInfoMapVec::validPositions (std::string const& var) const {
   std::vector<size_t> valid;
 
-  for (size_t i = 0; i < _rangeInfoMapVec.size(); i++) {
+  size_t const n = _rangeInfoMapVec.size();
+
+  for (size_t i = 0; i < n; i++) {
     if (_rangeInfoMapVec[i]->isValid(var)) {
       valid.emplace_back(i);
     }
diff --git a/arangod/Aql/RangeInfo.h b/arangod/Aql/RangeInfo.h
index 1e390b2427..02662b1ddd 100644
--- a/arangod/Aql/RangeInfo.h
+++ b/arangod/Aql/RangeInfo.h
@@ -373,8 +373,8 @@ namespace triagens {
 
         RangeInfo (std::string const& var,
                    std::string const& attr,
-                   RangeInfoBound low, 
-                   RangeInfoBound high,
+                   RangeInfoBound const& low, 
+                   RangeInfoBound const& high,
                    bool equality)
           : _var(var), 
             _attr(attr), 
@@ -414,6 +414,28 @@ namespace triagens {
             }
           }
         }
+        
+        RangeInfo (std::string const& var,
+                   std::string const& attr,
+                   RangeInfoBound const& bound) 
+          : _var(var), 
+            _attr(attr), 
+            _valid(true), 
+            _defined(true),
+            _equality(true) {
+
+          // must be an equality here!
+          TRI_ASSERT(bound.inclusive());
+
+          if (bound.isConstant()) {
+            _lowConst.assign(bound);
+            _highConst.assign(bound);
+          }
+          else {
+            _lows.emplace_back(bound);
+            _highs.emplace_back(bound);
+          }
+        }
 
         RangeInfo (std::string const& var,
                    std::string const& attr)